Question

A separate foul sewer network drains an urban area comprising residential housing for 55,000 people, a secondary school of 500students and a shopping arcade covering an area of 35,000m2.The volumes of wastewater discharged to the network from each source are 150l/p/d (housing), 170l/pupil/d (school) and 4 l/m2/d (shops).

(a)Calculate the dry weather flow (l/s) in the foul sewer, stating any assumptionsyou have made.[5](b)Calculate the peak flow rate of wastewater using the approaches of Fair and Geyer, Harmon and Gaines. Compare your answer to whatwould be obtained if the BS EN 752approach was used.[10]You are reminded that:DWF = PG + I + EHarmonfactor: 1+14/(4+√P)Gainesfactor: 5.16Q-0.060Fair and Geyer: 4Q-0.154

Answer 1